The acquisition gives Fox greater scale in streaming. The company previously bought Tubi, a free, ad-supported service. Roku distributes other streaming services through connected TVs and devices and also operates its own ad-supported Roku Channel.

Fox said Friday that the deal accelerates its digital strategy and expands its focus on high-growth streaming and connected-TV businesses. Roku founder Anthony Wood will join Fox’s board and become co-chair of Fox Digital Platforms, a newly formed division that includes Roku, Tubi, Fox One, Red Seat Ventures and other digital products and services.

Wood will lead the division alongside Paul Cheesbrough, who becomes its co-chair and chief executive officer. The deal closed after the Justice Department requested additional information from the companies about the transaction in September. Fox and News Corp., the parent of The Wall Street Journal, share common ownership.